For measuring the temperature within an air duct, a 3107 might be a better option. The 3108 is a hand-held probe with a long metal tip. It's meant for things like sticking it into a piece of meat, or soil. The 3107 is much smaller, you could drill a small hole in the duct, insert 1/2" of the sensor, and apply some foil tape over top.
The output of a thermocouple can't be directly plugged into an interface kit, it needs to be plugged in to either a 1048, or 1051.
The pressure sensor might work for airflow. You would either place the entire sensor inside the duct, or connect a small tube over top of the sensing element, and fasten this to the duct. You would then need to measure the atmospheric air pressure, use that as a base line, and read the pressure within your pipe. The pressure may be too small to properly measure though, depending on your air flow.